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arXiv · 1410.3686

The magneto-structural relationship in the tetrahedral spin chain oxide CsCoO$_2$

N. Z. Ali·R. C. Williams·F. Xiao·S. J. Clark·T. Lancaster·S. J. Blundell·D. V. Sheptyakov·M. Jansen
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Abstract

We have investigated the structural and magnetic transitions in CsCoO$_2$ using calorimetric measurements, neutron powder diffraction (NPD), density functional theory (DFT) calculations and muon-spin relaxation ($\mu$SR) measurements. CsCoO$_2$ exhibits three-dimensional long-range antiferromagnetic (AFM) order at 424~K, resulting in antiferromagnetic alignment of chains of ferromagnetically ordered Co-Co spin dimers. Although there is no change in magnetic structure around a structural transition at $T^{*}=100$~K, the resulting bifurcation of corner-shared Co--O--Co bond angles causes a weakening of the AFM interaction for one set of bonds along the chains. Consequently, the system undergoes a complex freezing out of relaxation processes on cooling.

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N. Z. Ali, R. C. Williams, F. Xiao, S. J. Clark, T. Lancaster, S. J. Blundell, D. V. Sheptyakov, M. Jansen. 2014-10-14. The magneto-structural relationship in the tetrahedral spin chain oxide CsCoO$_2$. https://doi.org/10.1103/physrevb.91.024419

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